Production of nitrogen-phosphorus compounds

ABSTRACT

A VAPOR PHASE REACTION PROCESS FOR PRODUCTION OF CONCENTRATED NITROGEN-PHOSPHORUS COMPOSITIONS. THE PROCESS INVOLVES SIMULTANEOUS REACTION OF ELEMENTAL PHOSPHORUS WITH A LOW PROPORTION OF INPUT AMMONIA AND AN EXCESS OF OXYGEN (AIR) IN A SINGLE-STAGE REACTOR. IMPUT OXYGEN (AIR) IS IN THE RANGE FROM GREATER THAN ABOUT 120 PERCENT UP TO ABOUT 800 PERCENT (ALL PERCENTS BY WEIGHT), AND MOST PREFERABLY 375 PERCENT OF THAT REQUIRED TO YIELD A O2:P4 MOLE RATIO OF 5. THE QUANTITY OF INPUT AMMONIA IS IN THE RANGE FROM GREATER THAN ABOUT 50 AND LESS THAN ABOUT 80 PERCENT OF THAT REQUIRED TO YIELD A N:P ATOMIC RATIO OF 2. THE REACTOR (TUB) IS MAINTAINED AT ABOUT 500* TO 1300*F. AND HAS A MAXIMUM SURFACE AREA:VOLUME RATIO OF ABOUT 0.8 IN.2/IN.3. RETENTION TIME OF GASES IN REACTOR RANGES FROM ABOUT 0.5 TO 3.5 SECONDS AT OPERATING CONDITIONS, BUT 1 SECOND IS MOST PREFERED. PRODUCT OF THE REACTION GASES IS COLLECTED AS DRY, WHITE, AMORPHOUS SOLID. PRODUCTS CONTAIN 14 TO 16 PERCENT N, 31 TO 33 PERCENT P, AND UP TO 91 PERCENT TOTAL PLANT NUTRIENT CONTENT (N+P2O5 EQUIVALENT). WATER SOLUBILITY OF THE SOLID PRODUCTS IS IN THE RANGE FROM ABOUT 90 TO 100 PERCENT. GREENHOUSE TESTS INDICATE THAT THE PRODUCTS ARE FULLY EFFECTIVE AS FERTILIZER.



